Adobe Photoshop Elements is ideal for the casual photographer, giving a decent organiser and plenty of more advanced editing tools to tweak the images. It is also one of the programs many photography magazines give tutorials for fixing.
Until 1st June Adobe are offering up to 25% off the price (for some reason they are now charging the same price for full and upgrades) giving a download price of £59.23 or a delivered box price for £61.93
Should also be able to get extra 10% off using TopCashBack or Quidco.
edit: link updated as it didn't appear to go to the right page all the time